Natural killer cells target:

These Gram-positive pleomorphic bacteria are toxin producers that cause formation of a pseudomembrane in the throat that can restrict airflow. This pathogen is

A.

Bordetella pertussis

B.

Streptococcus pyogenes

C.

Corynebacterium diphtheriae

D.

Neisseria meningitidis

E.

Streptococcus pneumoniae

Use the following scenario to answer question.

Island chains are known to occur along the borders of the earth’s large land plates. For example, both the Hawaiian and Galapagos Islands were born from the intense volcanic activity generated along the Pacific Ocean’s “Ring of Fire”. Hence, the number and placement of the islands can tell us approximately how many of the underwater volcanoes made islands and in what direction the plates are moving. Once formed, an island, then undergoes colonization by living organisms. We often describe a successful colonization event as one where the species lands, breeds and its offspring remain on the island to repeat its life cycle. In the case of Krakatau, which is a volcanic island in Indonesia, we have many recordings of its recolonization by life forms after the 1883 eruption which wiped the island clean of all preceding life forms. One of the first groups of organisms to colonize was that of spiders and insects.

11.What type of selection pressure would enhance the survival of the spiders and insects once they landed on the new Krakatau Island? Why? (i.e. divergent, convergent)

12.What kind of selection pressure would prevent the successful colonization by insects and spiders? Why?

2. List the different types of electron carriers within the electron transport system. For every pair of electrons each complex transfers, determine how many protons are translocated.

Biofilm formation by staphylococcus epidermidis

Describe the reaction of gluconeogenesis and for each step explain the type of reaction, enzyme involved, substrate and product, if the reaction is reversible or irreversible, any coenzyme or prosthetic group involved, and location.

Which statement among A-E is false concerning digestive system and gastrointestinal (GI) tract infections?

Describe the reaction of the citric acid cycle and for each step explain the type of reaction, enzyme involved, substrate and product, if the reaction is reversible or irreversible, any coenzyme or prosthetic group involved, and location.

In animal tissue, the rate of conversion of pyruvate of acetyl-CoA is regulated by the ratio of active, phosphorylated pyruvate dehydrogenase to inactive, unphosphorylated pyruvate dehydrogenase (PDG) complex. Explain the impact of the following regulators on the activity of pyruvate dehydrogenase complex in animal tissue extracts when treated with:

- high concentrations of acetyl-CoA

Explain how a white blood cell (leukocyte) uses protein-sugar interactions within a blood vessel to find the site of inflammation. Specify which proteins are involved in binding to which types of sugars during this process, and on which surface each of these ligands & receptors would be found

Describe the similarities and differences in chemiosmosis between oxidative phosphorylation in mitochondria and photophosphorylation in chloroplasts.

Part A: Punnett Squares

I. Monohybrid Crosses

1. In pea plants yellow peas (A) are dominant to green peas (a). Show a cross between two heterozygous yellow pea plants (Aa x Aa).

What is the genotypic ratio of the offspring? _______ AA : _______ Aa: _________ aa

What is the phenotypic ratio of the offspring? _______ Yellow: ________ Green

Part B: Using the Chi-square (χ2) analysis

9. In Parent 1 (P1) corn plants, the color purple is dominant to yellow, and round shape is dominant to wrinkled, which is why both Filial (F1) generation corn plants have the purple and round phenotypes, even when one of the parents (P1) is yellow and wrinkled.

The cross below (F1 x F1) produced the F2 generation corn that you are seeing in Figure 1. Determine the phenotypic ratios of the offspring of this cross: A cross between two F1 generation (heterozygous purple and heterozygous round) corn plants.

Phenotypic Ratio: _____: _____:_____:_____ (This is your hypothesis: The corn in Figure 1 has this ratio.)

Explain the relationship between the measurement of 2-deoxyadenosine and how this is being used to determine the amount of DNA in the experiment that uses diphenylamine reaction

Cystic fibrosis (CF) is caused by a genetic mutation resulting in defective proteins in secretory cells, mainly in the epithelial lining of the respiratory tract. The one in every 2,000 Caucasian babies who has the disease is homozygous for the recessive mutant. Although medical treatment is becoming more effective, in the past, most children with CF died before their teens. About 20 Caucasian in 2,000 are carriers of the trait, having one mutant and one normal allele, but they do not develop the disease. According to rules of population genetics, the frequency of the homozygous recessive genotype should be rarer than it is. What is one possible explanation for the unusually high frequency of this allele in Caucasian population?